Yabuki Joe is left downhearted and hopeless after a certain tragic event. In attempt to put the past behind him, Joe leaves the gym behind and begins wandering. On his travels he comes across the likes of Wolf Kanagushi and Goromaki Gondo, men who unintentionally fan the dying embers inside him, leading him to putting his wanderings to an end. His return home puts Joe back on the path to boxing, but unknown to himself and his trainer, he now suffers deep-set issues holding him back from fighting. In attempt to quell those issues, Carlos Rivera, a world renowned boxer is invited from Venezuela to help Joe recover.

Tousuke Rokudou is a first-year attending Aomori High, a school full of delinquents. He is often bullied by his classmates due to his incompatibility with their behavior, the only exceptions being his two good friends who are also social outcasts. Frustrated at the way they are treated, the three wish they could stand up and claim the fun, peaceful school life of their dreams. However, Tousuke's life takes a drastic turn when he receives a package from his late grandfather containing their family heirloom, a scroll said to possess the power to save him from impending danger. Upon holding the scroll, a sudden glow emanates, leaving a strange mark on Tousuke's forehead. Thinking that he's received the means to free himself and his friends from their daily treatment, Tousuke is shocked to find out that its effects are far different than what he had imagined. Although his bullying continues, he realizes that the mark from the scroll acts as a charm, capturing the hearts of delinquent girls—in particular, Ranna Himawari, the strongest of them all.

Miki Takekasa is an introverted high schooler who does not socialize with her classmates. However, she wants to know what fun really is, waiting for someone who could help her understand its true meaning. One day after school, she crosses paths with her classmate Aya Takayashiki, who takes her on a little adventure. Miki discovers wonders she had never seen before, opening a way to change her withdrawn life. On their way home, Miki and Aya see their class representative Midori Oono entering Saikoro Club, a store specializing in board games. After trying out a German board game, Miki soon understands the kind of fun she had been looking for: playing various games after school along with the friends and acquaintances she makes from her newfound pleasure.

In a world overtaken by war and conflict, Hypnosis Microphones—devices through which a user channels lyrics that can affect the listener's brain and even cause physical damage—were introduced to the masses by the Party of Words. Revolutionizing warfare, Hypnosis Mics have transformed words and music into the sole weapons used by gangsters, terrorists, and the military, with physical weapons having been banned from use. As a result of swooping in during the chaos, the all-female Party of Words rules over the Japanese government. Women in Japan now live in Chuuouku, while men battle over surrounding territories outside the ward through rap battles. With intentions unknown, the Party of Words begins to gather the former members of the now-disbanded legendary rap crew The Dirty Dawg to fight not for territory or war, but for their respective crew's pride and honor in the greatest rap battle of all time. The first Division Rap Battle is about to commence, and practice is not something these rappers are going to need.